Method and mechanism for aligning glued carton blanks



July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22,1963 3 Sheets-Sheet 1 July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22,1963 3 Sheets-Sheet 2 July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22,1963 3 Sheets-Sheet 3 United States Patent 0 This invention relates to amethod and a mechanism for aligning carton blanks and the like which arec0ntinuously advanced one after the other in a machine while passing afolding device in which the side parts of the blank are folded in towardthe central part thereof and glued together, during which operation anundesirable distortion of the edges of the side parts relative to theedges of the central part is likely to occur. The aligning operation isintended to be performed before the adhesive has completely dried, andthe object of this invention is to provide an improved method and animproved mechanism for aligning the glued carton blanks.

As previously known aligning mechanism comprises a stop member towardwhich the blanks are fed and a jogging member located ahead of the stopmember at a distance therefrom equal to the length of a carton, thejogging member engaging the trailing edges of the carton blank and beingadapted to force the blanks toward the stop member. Generally, thisoperation takes place while the carton blanks are being fed horizontallyto the aligning station on a conveyor consisting of rubber belts or thelike from which they are advanced during alignment to conveyor whichmakes an angle of 90 with the first named conveyor.

In this mechanism the jogging member consists of a relatively long,movable vertical plate adapted to make an oscillating movement such thatthe carton blanks during their forward movement are subjected to aplurality of impacts between the jogging member and the stop memberunder the action of which the aligning operation is performed.Consequently, this known mechanism is based on the principle that thecarton blanks are horizontally advancing during the aligning operation.

However, this method of aligning results in a plurality of considerableinconveniences. Since the carton blanks must have time to dry before thefinal stacking and the discharge of the finishing stack can take place,the most important disadvantage consists in that the conveyor for thecarton blanks advanced in rapid succession must be of a considerablelength. If the adhesive has not dried sufficiently there arises the riskof a renewed distortion of the side parts relative to the main part ofthe blanks because of the stresses acting on the carton blanks duringthe stacking operation. In view of the high velocity at which the cartonblanks are advancing on the conveyor they will travel a considerabledistance during the time required for drying, and the length of thecarton l manufacturing machine has to be adapted accordingly in order topermit the desired high advancing velocity.

The above inconvenience is entirely eliminated by the method accordingto the present invention which is characterized by placing the blanksafter the gluing operation and before the adhesive has dried, in astack, actuating the leading and trailing edges of the blanks at leastas they enter the stack by jogging members adapted to urge said leadingand trailing edges to parallel positions, and

" retaining the blanks in the stack until the adhesive has dried enoughto have the positions of said edges definitely fixed.

Due to the fact that the carton blanks form a substantially verticalstack during the time required for the 3,Il9d,l2 Patented July 13, 1965adhesive to dry sufficiently it will be obvious that the horizontallength of the carton manufacturing machine can be considerably reducedas compared with previously known similar machines. In addition to thereduction of the required space for the machine the manufacturing costof the machine is considerably reduced due to the fact that a greatnumber of rollers, rubber belts and other appertaining members ofconventional machines can be omitted.

Further, the aligning operation can be performed in an improved manner,since the carton blanks can be aligned by elements forming part of thealigning mechanism all the time during which the carton blanks arepassing through the stack. In other words in using the method accordingto the present invention the blanks have no possibility to resume theirprevious non-aligned form before the adhesive has dried enough to havethe carton blanks fixed.

Supposing that it were desired to double the productivity of a cartonmanufacturing machine by doubling the feeding speed and assuming otherfactors to be constant it will be obvious that in case of a conventionalmachine in which the length of the conveyor beyond the aligningmechanism is for instance 22 yards the length of the conveyor had to beincreased to 44 yards. In contrast thereto, in a mechanism according tothe invention it would merely be necessary to increase the height of thestack from for instance 3 feet and 4 inches to 6 feet and 8 incheswhereas the rest of the machine could remain unchanged.

The aligning mechanism is preferably provided at the stop member with aguide for correct feeding the leading edge of the carton blank towardthe stop member. By way of example this guide may consist of a curvedplate which forces the leading edge of the carton blank to be alignedagainst the stop member between the plate and the uppermost carton blankof the stack resulting in that the leading edge of each blank will comeinto contact with the stop member at substantially the same place.Consequently, the. distance between the jogging member and the stopmember which should be variable in accordance with the sizes of thecarton blanks can be determined in exact conformity with the blanks soas to obtain a very favourable result of the aligning mechanism.

The jogging member may consist of a toothed rotary roller the teeth ofwhich clutch the trailing edge of a blank and move said edge forward anddownward along the arc so as to force the leading edge against the stopmember and to align it whereupon during continued movement of thetoothed roller the trailing edge of the carton blank is disengagedtherefrom.

The jogging device may instead comprise two or more substantiallyvertical plates adapted to oscillate in an oblique forward and inwarddirection toward each other while oscillatingly urging the leading edgesof the blanks against the stop member.

However, in accordance with a preferred embodiment the aligningmechanism is constituted by a combination of the two above named joggingdevices, the toothed rollers being preferably adapted for coarsealignment and the vertical plates being adapted for fine alignment ofthe carton blanks.

This double aligning operation has proved to be very successful.Further, the parts of which the aligning mechanism consists are veryeasy to manufacture and the necessary movements of the parts can beobtained in a simple manner. In particular, the continuously workingvertical plates result in that the carton blanks in the stack aresubjected to a continuous aligning action during all the time requiredfor fixing the carton blanks a this being an essential condition of thefavourable result of the aligning operation.

Other features and advantages of this invention will appear from thefollowing detailed description of an embodiment thereof. Thespecification describes an example only of the invention with referenceto the annexed drawing in which FIGS. 1a and 1b are lateral elevationsof the fore and intermediate part respectively of a carton manufacturingmachine. In FIG. 2 which is a top view of the same parts severalirrelevant elements are omitted and other elements, such as the verticalplates are partly exposed for the sake of clearness although they areconcealed in reality. Further, the figures have been shortened by acentral section. FIGS. 3 and 4 illustrate to an enlarged scale someparts important to the invent-ion and corresponding to similar parts inFIGS. 1b and 2, respectively.

Referring to the drawing, M denotes the uppermost carton blank in thestack from which the blanks are fed to the carton manufacturing machine.The remaining blanks in the stack are denoted at 112, 1c and 1d the lastnamed blank 1d being the lowermost blank which is about to be dischargedfrom the stack. denotes the lowermost but one blank to be forwardedafter the blank 1d. A carton blank the tab 1x of which is coated withadhesive is denoted at 12. A carton blank the side parts of which areturned down to vertical positions if denoted at 1 and 1g denotes acarton blank the side parts of which are being folded together. llhdenotes a carton blank which in a short time arrives at the aligningmechanism, 1i denotes a blank during coarse alignment and the cartonblanks piled one on top of the other in the fine alignment mechanism aredenoted at lj. Finally, 1k denotes a completely aligned carton blankdischarged from the stack. After a blank has arrived on a conveyoradhesive is applied to the tab 1x at one of the side parts of the cartonblank (FIG. 2) by means of a roller 17 which receives adhesive from acontainer 18. In FIG. 1 the carton blank to which adhesive is applied isdenoted at 1e. After application of the adhesive folding of the sideparts 132 and lz is started and effected by means of two helical rods 19while the blanks are travelling forward on the continuously runningrubber belts 26. In FIG. 1 the carton blanks If and 1g are shown indifferent stages of the folding operation.

I It should be pointed out that the carton manufacturing machineillustrated is devised such that the side parts are folded downward,this being of great advantage as compared with construct-ions ofpreviously known design in which said parts are folded upwards. Due tothe downward folding the carton blanks can be delivered directly to themachine from a printing press where inscriptions and/ or pictures areapplied without the necessity of turn ing over the blanks. Thisimprovement is due to the special design of the folding rods 19 shown inFIGS. 1a and 1b.

After the side parts ly and 12: have started the folding -movementoutward each other the central part comprising the sections 1p and lq isguided by bordering belts 25. Should the central part of the cartonblank during the folding operation of the side parts have deviated fromthe direction of feed this fault will be corrected by the borderingbelts. These belts consequently assist in minimizing distortion of theedges of the side parts relative to'the edges of the central part duringthe final folding operation which precedes the final gluing. It is notpossible, however, entirely to eliminate such distortion before theblank passes between pressure rollers 2% where the previously coated tab1x of the side part 1y of the blank is bonded to the opposite side partlz. Consequently a certain distortion of the side parts relative to thecentral part will remain after the blank has passed the pressure rollers26. In the technical language it is a common saying that the side partsare forming a snowplough.

The purpose of the aligning operation is to eliminate this distortion soas to give the carton blanks the same form as the blank 1k which meansan exact alignment of the central part of the carton blank with the sideparts or wings thereof. The aligning mechanism consists of an abutmentor stop member 3 and a jogging device located at a distance therefromequal to the length of a carton and comprising two complementaryelements. One of these elements is the toothed roller 4, (FIGS. 3 and 4)and the other element comprises vertical plates 5 (FIG. 4). The toothedroller is continuously rotating whereas the vertical plates are adaptedto oscillate in an oblique forward and inward direction toward eachother. During rotation of the toothed roller 4 the teeth thereof clutchthe trailing edge of the carton blank 11' and move this edge forward anddownward along an are so as to force the leading edge into contact withthe stop member 3. As a result, the carton blank will be momentarilyheld between the toothed roller and the stop member, and first of allthe oblique side parts will be forced against the stop member so as tocounteract the distortion. After the point of the roller which engagesthe trailing edge of the blank has passed its foremost position adownward vertical movement is imparted to the trailing edge and uponcontinued rotation of the toothed roller the trailing edge of the blankwill be disengaged therefrom and moved down onto the stack c of cartonblanks. It will be seen that the toothed roller forms part of a stackingdevice by means of which and under the action of gravity the cartonblanks are moved downward and form a stack. During their downwardmovement in the stack the blanks are then continuously acted upon by thevertical plates.

If after the primary alignment by the toothed roller 21 certaindistortion remains it will be eliminated by the vertical plates whichsupplement the coarse aligning effected by the toothed roller. Thedistance between the stop member and the toothed roller may even be sogreat that on purpose a certain distortion remains after the coarsealignment by the toothed roller 4 which distortion is then eliminated bythe fine alignment device in the form of the vertical plates.

At the top of the stop member there is provided a guide 2 which guidesthe leading edge of the entering blank such that the blank will be movedtoward the upper end of the stop member between the guide and theuppermost blank of the stack. The guide consists of an upwardly concaveplate. Associated with the toothed roller 4 is a plurality of springleaves 6 which assist in guiding the leading edge of the blanks as itmoves toward the stop member and also facilitate engagement of thetoothed roller with the trailing edge of the blank.

After coarse alignment between the toothed roller 4 and the stop member3 the blank is moved down between a plurality of substantially verticalplates 7. The stack of blanks is disposed between the plates 7 and thestop member. The distance between the rear plate 7 and the stop member 3is slightly greater than the length of the carton blank so that there issufficient place between the rear plate 7 and the stop member 3 even forthe only coarsely aligned blanks having still a certain distortionbetween the side parts ily and lz and the part 1p, 1q. As mentionedabove the carton blanks are acted upon during their downward movement inthe stack by the fine alignment device in the form of the verticalplates 5 which oscillate in an oblique forward and inward directiontoward each other. Similar to the preceding coarse aligning operationthe leading edges of the blanks are forced against the stop member,which per se results in an aligning operation. However, the forward andinward movement of the plates results in an additional aligning movementbecause of the fact that the plates directly act upon the oblique lowerside parts ly and lz of the coarsely aligned carton blankin a directionin which they shall move to secure complete alignment of the blank. As aresult the carton blank will be completely aligned as soon as it comesinto contact with the fine aligning device at the upper part of thestack. Any tendency of the side parts of the carton blank to return totheir previous nonaligned positions is counteracted by the fine aligningmembers 5 all the time required for the movement of the blank from thetop to the bottom of the stack during which movement the adhesive hastime to dry enough to have the positions of the edges of the blankdefinitely fixed.

The movement of the fine aligning device 5 is derived from twoeccentrically mounted pins 23 (FIG. 4) which act upon the rear edges ofhorizontal rods 22 connected to the plates 5. The rods are directedtoward each other and make an angle of about 45 with the direction offeed. The movement of the rods is guided by a plurality of rotaryrollers 24. The return movement from the foremost position takes placeunder the action of springs indicated in the drawing. Alternatively, therods may be provided at the eccentric pins 23 in which case the rearrollers 24 are omitted. The eccentric pins rotate at a comparativelyhigh speed so as to impart to the vertical plate a relatively rapidoscillating motion in an oblique forward and inward direction.

The finally aligned carton blanks are discharged substantiallyhorizontally one by one from the lower part of the stack by means of adischarging device 8, 9, 10, which is based on the same principle as thefeeding device at the fore part of the machine, but is not devised in anexactly similar manner.

The blanks are discharged substantially in timed relation to thedownward movement of the coarsely aligned blanks to the top of thestack.

A detent 11 acts to prevent discharge of blanks in the event of theheight of the stack of blanks being smaller than a predetermined value.Otherwise the carton blanks would pass through the stack before theadhesive has sufiiciently dried. The guide 2 at the upper part of thestop member is pivotally mounted on a horizontal shaft and devised as afeeler 12 which has the double function of guiding the movement of theleading edge of the blank toward the stop member and of ascertaining theheight of the stack. If there are too few cartonblanks in the stack,that is, if the stack is too low, the feeler 12 falls under the actionof gravity forward and downward and thereby sends a signal to the detent11 which puts the discharging device out of function until the stack isof sufficient height. In the embodiment illustrated in the drawing thedetent consists of a spring leave 11 provided at one end of a lever 12.At the other end of the swingable lever 12 there is secured the armature14 of an electromagnet 15. As mentioned above if the height of the stackis not sufificient the combined guide 2 and feeler 12 are loweredforward under the action of gravity with the result that an impulse isemitted to the electromagnet 15, which attracts the armature 14. Theother end of the lever moves upwards and prevents the lowermost blankfrom coming into contact with the continuously running rubber beltsbelow the stack so that no blank can be discharged from the stack. Assoon as the stack is sufficiently high the current to the electromagnetis broken whereupon the lowermost blank can be discharged in the regularmanner.

The finally aligned carton blank 1k is then fed to a stacker, not shownin the drawings.

The blanks are advanced to the stop member 3 by means of the pressurerollers which also press the side parts of the blanks against thecentral part prior to the aligning operation. A rubber roller 21cooperating with the toothed coarse aligning roller 4 also assists inadvancing the carton blank toward the stop member except for the verylast step of movement during which the toothed roller 4 solely feeds andsimultaneously aligns the carton blanks.

The stop member 3, guide 2, detent 11 and associated members are movablerelative to the aligning members to permit adjustment in accordance withditferent sizes of cartons. If desired, the vertical extension of thestop member 3 and the rear plates 7 may be varied to obtain differentheights ofthe stack. To this end, the stop member and the rear plate mayconsist of a plurality of detachable parts which are removable andexchangeable for other corresponding parts of greater or smallerlengths.

resilient so that the blanks afterhaving been moved down' by the toothedroller 4 are held between. the rear plate and the top member and thenare moved down by the next succeeding blank after the correspondingalignment and downward movement thereof. If the stop member is resilientit may consist of a fixed part and a plurality of smaller resilientparts projecting therefnom which resilient parts during the aligningoperation of a blank are forced back toward the fixed part and afterdownward movement of the rear edges of the blanks into contact with therear plate keep the blanks in engagement with the rear plate. It willalso be understood that the carton blanks can be brought to passupwardly in the stack in which case a toothed roller disposed below thestack can be used as an aligning member. In this modification the stopmember is suitably of different construction and may comprise, forexample, a plurality of dogs or the like which are movable downwardbelow the conveyor as the final stack is released.

It will also be seen from the drawing that, for instance, the stopmember and the rear plate are not exactly vertical but slightly sloping.The slope is due to the construction of the other parts of the machineand is not relevant to the present invention. Although not specificallyindicated in this connection the words vertical and horizontal generallyinclude the words substantially vertical and substantially horizontal inthe specification and claims.

What is claimed is:

l. A mechanism for squaring up carton blanks and similar relativelystiff blanks having fold or crease lines, said blanks being continuouslyadvanced one after the other in a machine while passing a folding devicein which the side parts of the blanks are folded in toward the centralpart thereof and glued together during which operation an undesireddistortion of the edges of the side parts relative to the edges of thecentral part tends to occur, which mechanism comprises a fixed stopmember toward which the blanks are fed; a profiled rotary roller locatedat a distance from the stop member equalling the length of a blank, saidroller being adapted to clutch the trailing edges of a blank and to movesaid edges forward along an are so as to force the leading edge of theblank against the stop member to squareup the blank, said roller uponcontinued rotation delivering the blanks to a stack.

2. A mechanism as defined in claim 1, said profiled roller being locatedabove the stack.

3. A mechanism as defined in claim 1, in which said profiled roller is atoothed roller.

4. A mechanism as defined in claim 1, in which said I profiled roller isa fluted roller.

5. A mechanism as defined in claim 1 and comprising at least twosubstantially vertical plates located at a distance from the top memberequalling the length of a blank, said plates being adapted to oscillatein an oblique forward and inward direction toward each other whileoscillatingly urging the leading edges of the blanks in the stackagainst the stop member.

6. A mechanism as defined in claim 1,. and compris ing spring meansassociated with the rotary roller and adapted to guide the leading edgesof the blanks as they pass toward the stop member and to facilitateengagement of the profile of the roller with the trailing edges of theblanks.

7. A mechanism as defined in claim 1 and comprising guide means formoving the leading edges of the carton blanks toward the stop member.

3. A mechanism as defined in claim 1 and comprising a fixedsubstantially vertical rear plate at a distance from the stop memberslightly exceeding the length of a blank, the stack of blanks beingaccommodatable in the space between said fixed rear plate and said stopmember.

9. A mechanism as defined in claim 2, and compris- References Cited bythe Examiner UNITED STATES PATENTS 3,030,867 4/62 Wright 93-36 3,087,7254/63 Duncan 27171 FRANK E. BAILEY, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,194,126 July 13, 1965 Olof Einar Larsson It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 6, line 68, for "top" read stop Signed and sealed this 21st dayof December 1965.

(SEAL) Attest ERNEST W. SW'IDER Attesting Officer EDWARD J. BRENNERCommissioner of Patents

1. A MECHANISM FOR SQUARING UP CARTON BLANKS AND SIMILAR RELATIVELYSTIFF BLANKS HAVING FOLD OR CREASE LINES, SAID BLANKS BEING CONTINUOUSLYADVANCED ONE AFTER THE OTHER IN A MACHINE WHILE PASSING A FOLDING DEVICEIN WHICH THE SIDE PARTS OF THE BLANKS ARE FOLDED IN TOWARD THE CENTRALPART THEREOF AND GLUED TOGETHER DURING WHICH OPERATION AN UNDESIREDDISTORTION OF THE EDGES OF THE SIDE PARTS RELATIVE TO THE EDGES OF THECENTRAL PART TENDS TO OCCUR, WHICH MECHANISM COMPRISES A FIXED STOP MEM-